Ian Brennan has mapped out exactly when Netflix’s Monster anthology will conclude.
The showrunner, who created the true-crime series alongside Ryan Murphy, told The Hollywood Reporter that both men have settled on a firm endpoint for the franchise even as they continue weighing which killers deserve the spotlight. Brennan, who has written all four seasons since The Jeffrey Dahmer Story debuted in 2022, said he and Murphy want to cap the run at 10 installments total.
The pair’s latest entry, Monster: The Lizzie Borden Story, hit Netflix on September 17. It follows The Jeffrey Dahmer Story, The Menendez Brothers, and last year’s The Ed Gein Story. Brennan revealed that landing on Borden required cycling through several other candidates first, including one very recent case.
“We were trying to crack the Luigi [Mangione] story,” he said, referring to the former software engineer charged with killing UnitedHealthcare CEO Brian Thompson in 2024. Brennan explained that they ultimately abandoned Mangione because the case felt too fresh.
The selection process remains deliberately fluid. “We never do,” Brennan said when asked whether they always have their next subject locked in. “We always switch. It’s always three or four different ones, and we toggle between.”
That hopper currently holds three possibilities, though Brennan cautioned that many candidates get discarded early. “You’d be surprised at how many subjects we start and then abandon, because it’s just not right,” he continued. “You can really tell when it’s wrong right away, because you’re asking people to spend seven or eight or nine or 10 hours getting inside this person’s head. They better be really interesting.”
When the right figure does emerge, the writing moves fast. “It’s a super organic writing process that goes very, very quickly,” Brennan said. “It’s very easy because you don’t have to invent all that much. You know where it’s going, you know the facts. So you’re more curating episodes, and the writing is effortless.”
He added that the true-crime format offers unexpected creative freedom within its constraints. “That’s a very surprising aspect of working in the true crime, how fun and enjoyable it is,” he said. “Because you sort of know what the story is, you get to be really creative inside those parameters in a way where, if you’re making stuff up from whole cloth, that can actually be much more laborious.”
The Lizzie Borden season dramatizes the 1892 axe murders of Andrew and Abby Borden in Fall River, Massachusetts, and the subsequent trial that made Lizzie an infamous figure in American criminal history despite her acquittal.
Brennan and Murphy’s 10-season target leaves six more killers’ stories to tell after Borden, with the creators continuing to sift through what Brennan called a “fairly exhaustive list” of possibilities.